There is not enough clearance to leave anything on the REV all the time.
As for the swivel, I was actually linking to their larger sewer hose holders, not the swivel one really. Thetford makes one that interests me...its a water propelled dump hose that goes into a 3/4" hose. Pretty cool.
sami-con also makes a "twist on" macerator. You would need to wire up 12v...but the small hose diameter would be much easier to store. (in theory)
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